Question

Item 4 Pete wants to mix 4 quarts of 20% orange juice concentrate with some 60% pineapple juice concentrate to get a 50% punch concentrate for a party. How much of the 60% pineapple juice concentrate should be used? (OMIT THE UNIT FOR YOUR ANSWER - ENTER THE NUMERIC VALUE ONLY.)

Answer 1

12 quarts of 60% pineapple juice concentrate should be used

Explanation:

Let the amount for the 60% be x

20% of 4 + 60% of x = 50% of (x + 4)

So we have;

0.2(4) + 0.6(x) = 0.5(x + 4)

0.8 + 0.6x = 0.5x + 2

0.6x-0.5x = 2-0.8

0.1x = 1.2

x = 1.2/0.1

x = 12